1 /* 2 * Copyright 2006 Sun Microsystems, Inc. All rights reserved. 3 * Use is subject to license terms. 4 */ 5 6 #ifndef _KRB5_DB2_DBQUEUE_H 7 #define _KRB5_DB2_DBQUEUE_H 8 9 #pragma ident "%Z%%M% %I% %E% SMI" 10 11 #ifdef __cplusplus 12 extern "C" { 13 #endif 14 15 /* 16 * Copyright (c) 1991, 1993 17 * The Regents of the University of California. All rights reserved. 18 * 19 * Redistribution and use in source and binary forms, with or without 20 * modification, are permitted provided that the following conditions 21 * are met: 22 * 1. Redistributions of source code must retain the above copyright 23 * notice, this list of conditions and the following disclaimer. 24 * 2. Redistributions in binary form must reproduce the above copyright 25 * notice, this list of conditions and the following disclaimer in the 26 * documentation and/or other materials provided with the distribution. 27 * 3. All advertising materials mentioning features or use of this software 28 * must display the following acknowledgement: 29 * This product includes software developed by the University of 30 * California, Berkeley and its contributors. 31 * 4. Neither the name of the University nor the names of its contributors 32 * may be used to endorse or promote products derived from this software 33 * without specific prior written permission. 34 * 35 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 36 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 37 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 38 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 39 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 40 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 41 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 42 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 43 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 44 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 45 * SUCH DAMAGE. 46 * 47 * @(#)queue.h 8.3 (Berkeley) 12/13/93 48 */ 49 50 #ifndef _QUEUE_H_ 51 #define _QUEUE_H_ 52 53 /* 54 * This file defines three types of data structures: lists, tail queues, 55 * and circular queues. 56 * 57 * A list is headed by a single forward pointer (or an array of forward 58 * pointers for a hash table header). The elements are doubly linked 59 * so that an arbitrary element can be removed without a need to 60 * traverse the list. New elements can be added to the list after 61 * an existing element or at the head of the list. A list may only be 62 * traversed in the forward direction. 63 * 64 * A tail queue is headed by a pair of pointers, one to the head of the 65 * list and the other to the tail of the list. The elements are doubly 66 * linked so that an arbitrary element can be removed without a need to 67 * traverse the list. New elements can be added to the list after 68 * an existing element, at the head of the list, or at the end of the 69 * list. A tail queue may only be traversed in the forward direction. 70 * 71 * A circle queue is headed by a pair of pointers, one to the head of the 72 * list and the other to the tail of the list. The elements are doubly 73 * linked so that an arbitrary element can be removed without a need to 74 * traverse the list. New elements can be added to the list before or after 75 * an existing element, at the head of the list, or at the end of the list. 76 * A circle queue may be traversed in either direction, but has a more 77 * complex end of list detection. 78 * 79 * For details on the use of these macros, see the queue(3) manual page. 80 */ 81 82 /* 83 * List definitions. 84 */ 85 #define LIST_HEAD(name, type) \ 86 struct name { \ 87 struct type *lh_first; /* first element */ \ 88 } 89 90 #define LIST_ENTRY(type) \ 91 struct { \ 92 struct type *le_next; /* next element */ \ 93 struct type **le_prev; /* address of previous next element */ \ 94 } 95 96 /* 97 * List functions. 98 */ 99 #define LIST_INIT(head) { \ 100 (head)->lh_first = NULL; \ 101 } 102 103 #define LIST_INSERT_AFTER(listelm, elm, field) { \ 104 if (((elm)->field.le_next = (listelm)->field.le_next) != NULL) \ 105 (listelm)->field.le_next->field.le_prev = \ 106 &(elm)->field.le_next; \ 107 (listelm)->field.le_next = (elm); \ 108 (elm)->field.le_prev = &(listelm)->field.le_next; \ 109 } 110 111 #define LIST_INSERT_HEAD(head, elm, field) { \ 112 if (((elm)->field.le_next = (head)->lh_first) != NULL) \ 113 (head)->lh_first->field.le_prev = &(elm)->field.le_next;\ 114 (head)->lh_first = (elm); \ 115 (elm)->field.le_prev = &(head)->lh_first; \ 116 } 117 118 #define LIST_REMOVE(elm, field) { \ 119 if ((elm)->field.le_next != NULL) \ 120 (elm)->field.le_next->field.le_prev = \ 121 (elm)->field.le_prev; \ 122 *(elm)->field.le_prev = (elm)->field.le_next; \ 123 } 124 125 /* 126 * Tail queue definitions. 127 */ 128 #define TAILQ_HEAD(name, type) \ 129 struct name { \ 130 struct type *tqh_first; /* first element */ \ 131 struct type **tqh_last; /* addr of last next element */ \ 132 } 133 134 #define TAILQ_ENTRY(type) \ 135 struct { \ 136 struct type *tqe_next; /* next element */ \ 137 struct type **tqe_prev; /* address of previous next element */ \ 138 } 139 140 /* 141 * Tail queue functions. 142 */ 143 #define TAILQ_INIT(head) { \ 144 (head)->tqh_first = NULL; \ 145 (head)->tqh_last = &(head)->tqh_first; \ 146 } 147 148 #define TAILQ_INSERT_HEAD(head, elm, field) { \ 149 if (((elm)->field.tqe_next = (head)->tqh_first) != NULL) \ 150 (elm)->field.tqe_next->field.tqe_prev = \ 151 &(elm)->field.tqe_next; \ 152 else \ 153 (head)->tqh_last = &(elm)->field.tqe_next; \ 154 (head)->tqh_first = (elm); \ 155 (elm)->field.tqe_prev = &(head)->tqh_first; \ 156 } 157 158 #define TAILQ_INSERT_TAIL(head, elm, field) { \ 159 (elm)->field.tqe_next = NULL; \ 160 (elm)->field.tqe_prev = (head)->tqh_last; \ 161 *(head)->tqh_last = (elm); \ 162 (head)->tqh_last = &(elm)->field.tqe_next; \ 163 } 164 165 #define TAILQ_INSERT_AFTER(head, listelm, elm, field) { \ 166 if (((elm)->field.tqe_next = (listelm)->field.tqe_next) != NULL)\ 167 (elm)->field.tqe_next->field.tqe_prev = \ 168 &(elm)->field.tqe_next; \ 169 else \ 170 (head)->tqh_last = &(elm)->field.tqe_next; \ 171 (listelm)->field.tqe_next = (elm); \ 172 (elm)->field.tqe_prev = &(listelm)->field.tqe_next; \ 173 } 174 175 #define TAILQ_REMOVE(head, elm, field) { \ 176 if (((elm)->field.tqe_next) != NULL) \ 177 (elm)->field.tqe_next->field.tqe_prev = \ 178 (elm)->field.tqe_prev; \ 179 else \ 180 (head)->tqh_last = (elm)->field.tqe_prev; \ 181 *(elm)->field.tqe_prev = (elm)->field.tqe_next; \ 182 } 183 184 /* 185 * Circular queue definitions. 186 */ 187 #define CIRCLEQ_HEAD(name, type) \ 188 struct name { \ 189 struct type *cqh_first; /* first element */ \ 190 struct type *cqh_last; /* last element */ \ 191 } 192 193 #define CIRCLEQ_ENTRY(type) \ 194 struct { \ 195 struct type *cqe_next; /* next element */ \ 196 struct type *cqe_prev; /* previous element */ \ 197 } 198 199 /* 200 * Circular queue functions. 201 */ 202 #define CIRCLEQ_INIT(head) { \ 203 (head)->cqh_first = (void *)(head); \ 204 (head)->cqh_last = (void *)(head); \ 205 } 206 207 #define CIRCLEQ_INSERT_AFTER(head, listelm, elm, field) { \ 208 (elm)->field.cqe_next = (listelm)->field.cqe_next; \ 209 (elm)->field.cqe_prev = (listelm); \ 210 if ((listelm)->field.cqe_next == (void *)(head)) \ 211 (head)->cqh_last = (elm); \ 212 else \ 213 (listelm)->field.cqe_next->field.cqe_prev = (elm); \ 214 (listelm)->field.cqe_next = (elm); \ 215 } 216 217 #define CIRCLEQ_INSERT_BEFORE(head, listelm, elm, field) { \ 218 (elm)->field.cqe_next = (listelm); \ 219 (elm)->field.cqe_prev = (listelm)->field.cqe_prev; \ 220 if ((listelm)->field.cqe_prev == (void *)(head)) \ 221 (head)->cqh_first = (elm); \ 222 else \ 223 (listelm)->field.cqe_prev->field.cqe_next = (elm); \ 224 (listelm)->field.cqe_prev = (elm); \ 225 } 226 227 #define CIRCLEQ_INSERT_HEAD(head, elm, field) { \ 228 (elm)->field.cqe_next = (head)->cqh_first; \ 229 (elm)->field.cqe_prev = (void *)(head); \ 230 if ((head)->cqh_last == (void *)(head)) \ 231 (head)->cqh_last = (elm); \ 232 else \ 233 (head)->cqh_first->field.cqe_prev = (elm); \ 234 (head)->cqh_first = (elm); \ 235 } 236 237 #define CIRCLEQ_INSERT_TAIL(head, elm, field) { \ 238 (elm)->field.cqe_next = (void *)(head); \ 239 (elm)->field.cqe_prev = (head)->cqh_last; \ 240 if ((head)->cqh_first == (void *)(head)) \ 241 (head)->cqh_first = (elm); \ 242 else \ 243 (head)->cqh_last->field.cqe_next = (elm); \ 244 (head)->cqh_last = (elm); \ 245 } 246 247 #define CIRCLEQ_REMOVE(head, elm, field) { \ 248 if ((elm)->field.cqe_next == (void *)(head)) \ 249 (head)->cqh_last = (elm)->field.cqe_prev; \ 250 else \ 251 (elm)->field.cqe_next->field.cqe_prev = \ 252 (elm)->field.cqe_prev; \ 253 if ((elm)->field.cqe_prev == (void *)(head)) \ 254 (head)->cqh_first = (elm)->field.cqe_next; \ 255 else \ 256 (elm)->field.cqe_prev->field.cqe_next = \ 257 (elm)->field.cqe_next; \ 258 } 259 #endif /* !_QUEUE_H_ */ 260 261 #ifdef __cplusplus 262 } 263 #endif 264 265 #endif /* !_KRB5_DB2_DBQUEUE_H */ 266